Combination fuel pump motor assembly with integral filter housing

ABSTRACT

A fuel pump motor system  10  for providing fuel to an engine includes a pump motor assembly  12  having a rotor  16  for generating a rotor magnetic field; a shaft  21  mounted with respect to the rotor such that rotation of the rotor rotates the shaft, an impeller  20  mounted to the shaft, and a stator  18  for generating a stator magnetic field. The stator is associated with the rotor such that interaction of the rotor magnetic field and the stator magnetic field causes the rotor and thus the shaft and impeller to rotate thereby moving fuel from an inlet  24  to an outlet  26  of the pump motor assembly. A filter structure  14  is integral with the pump motor assembly and shares a substantially sealed, non-porous barrier  25  therewith. The filter structure includes filtration media  28  constructed and arranged to filter fuel received from the outlet of the pump motor assembly prior to delivery to an engine.

This application is based on U.S. Provisional Application No. 60/683,713, filed on May 23, 2005 and claims the benefit thereof for priority purposes.

BACKGROUND OF THE INVENTION

In a vehicle fuel delivery system, a purpose of a fuel pump is to pressurize fuel within the system to enable a continuous supply of fuel to fuel injectors during engine operation. Fuel is typically filtered to protect the injectors' small orifices from plugging due to contaminants within the fuel that originates in a fuel tank.

Typically, a fuel filter is associated with an outlet of a fuel pump, but the filter is provided separate from the fuel pump. This configuration requires additional material due to the proximity of the filter to the pump and also requires additional manufacturing assembly steps.

There is a need to integrate a fuel filter with a fuel pump to eliminate the need for extra material and to reduce manufacturing assembly steps.

SUMMARY OF THE INVENTION

An object of the invention is to fulfill the need referred to above. In accordance with the principles of the present invention, this objective is achieved by providing a fuel pump motor system for delivering fuel to an engine. The system includes a pump motor assembly having a rotor for generating a rotor magnetic field; a shaft mounted with respect to the rotor such that rotation of the rotor rotates the shaft, an impeller mounted to the shaft, and a stator for generating a stator magnetic field. The stator is associated with the rotor such that interaction of the rotor magnetic field and the stator magnetic field causes the rotor and thus the shaft and impeller to rotate thereby moving fuel from an inlet to an outlet of the pump motor assembly. A filter structure is integral with the pump motor assembly and shares a substantially sealed, non-porous barrier therewith. The filter structure includes filtration media constructed and arranged to filter fuel received from the outlet of the pump motor assembly prior to delivery to an engine.

In accordance with another aspect of the invention, a method provides a fuel pump motor system for delivering fuel to an engine. The method provides a pump motor assembly including a motor having a shaft, and an impeller coupled to the shaft such that rotation of the shaft and impeller moves fuel from an inlet to an outlet of the pump motor assembly. A periphery of the pump motor assembly is generally surrounded with filter structure such that the filter structure shares a substantially sealed, non-porous barrier with the pump motor assembly. The filter structure includes filtration media constructed and arranged to filter fuel received from the outlet of the pump motor assembly prior to delivery to an engine.

Other objects, features and characteristics of the present invention, as well as the methods of operation and the functions of the related elements of the structure, the combination of parts and economics of manufacture will become more apparent upon consideration of the following detailed description and appended claims with reference to the accompanying drawings, all of which form a part of this specification.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood from the following detailed description of the preferred embodiments thereof, taken in conjunction with the accompanying drawings, wherein like reference numerals refer to like parts, in which:

FIG. 1 is a plan view of a fuel pump motor system, having a pump motor assembly and an integral filter structure, provided in accordance with the principles of the present invention.

FIG. 2 is a schematic, sectional view taken along the line 2-2 of FIG. 1.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

With reference to FIG. 1, a plan view of a fuel pump motor system is shown, generally indicated at 10, in accordance with the principles of the present invention. The system 10 is for delivering fuel such as gas or diesel to an engine of a vehicle. As best shown in FIG. 2, the system 10 includes an electric pump motor assembly, generally indicated at 12, and an integral filter structure or housing 14 generally surrounding a periphery of the pump motor assembly 12. The pump motor assembly 12 includes a rotor in the form of a conventional motor armature 16 having windings 17 that, when energized, generate a rotor magnetic field. A shaft 21 is carried by the rotor or armature 16 and is mounted for rotation by bearings 23 at each end thereof. A stator magnetic field is generated by permanent magnet structure (stator) in the form of one or more permanent magnets 18 fixed to an inside surface 19 of a wall 25 of the system 10, such that upon energizing the windings, interaction of the magnetic fields causes the armature 16 to rotate in the conventional manner. The rotor and stator define a motor of the pump motor assembly 12.

An impeller or turbine 20, mounted to an end of the shaft 21, is disposed in a pump chamber 22 for displacing fuel. Thus, when the armature 16 rotates, the shaft 21 and impeller 24 also rotate to cause fuel to move from a pump inlet 24, at one end of the system 10, to a pump outlet 26, at the other end of the system 10. A pump cover 30, mounted at the end of the system 10, covers electrical components for operating the pump motor assembly 12.

Although in the embodiment, the armature 16 is the rotating element (rotor), it can be appreciated that the pump motor assembly 12 can be configured such that the magnet structure 18 is the rotating element together with the shaft, with the armature 16 defining a stator that is fixed to wall 25.

As noted above, the filter structure or housing 14 is integral with the pump motor assembly 12 and defines a housing for the pump motor assembly 12. Thus, the filter housing 14 shares a substantially sealed, non-porous barrier (wall 25) with the pump motor assembly 12. The filter housing 14 includes filtration media 28. Thus, in one embodiment, fuel, indicated at arrow A, is directed from the outlet 26 (via structure not shown) to the media 28 and is filtered by the media 28. Thereafter, the filtered fuel exits outlet 32 of the filter housing 14 and is delivered to an engine (not shown). Alternatively, an opening 34 can be provided in the wall 25 and fuel, indicated at arrow B, can pass through the opening 34 and be filtered by the media 28 prior to exiting through outlet 32. Since the inside surface 19 of wall 25 is exposed to non-filtered fuel and the filtration media 28 is adjacent to the outside surface 27 of the wall 25, the wall 25 in the system 10 separates filtered and non-filtered fuel.

The proximity of the pump motor assembly 12 to the filter housing 14 eliminates the need for extra material and reduces manufacturing assembly steps. All components of the system 10 can be assembled uni-directionally and sealed in an appropriate fashion.

The foregoing preferred embodiments have been shown and described for the purposes of illustrating the structural and functional principles of the present invention, as well as illustrating the methods of employing the preferred embodiments and are subject to change without departing from such principles. Therefore, this invention includes all modifications encompassed within the spirit of the following claims. 

1. A fuel pump motor system for delivering fuel to an engine, the system comprising: a pump motor assembly comprising: a rotor for generating a rotor magnetic field, a shaft mounted with respect to the rotor such that rotation of the rotor rotates the shaft, an impeller mounted to the shaft, and a stator for generating a stator magnetic field, the stator being associated with the rotor such that interaction of the rotor magnetic field and the stator magnetic field causes the rotor and thus the shaft and impeller to rotate thereby moving fuel from an inlet to an outlet of the pump motor assembly, and a filter structure integral with the pump motor assembly and sharing a substantially sealed, non-porous barrier therewith, the filter structure including filtration media constructed and arranged to filter fuel received from the outlet of the pump motor assembly prior to delivery to an engine.
 2. The system of claim 1, wherein the filter structure is disposed generally about a periphery of the pump motor assembly to define a housing for the pump motor assembly.
 3. The system of claim 1, wherein the rotor includes an armature and windings, such that energizing the windings generates the rotor magnetic field, and wherein the stator includes permanent magnet structure generating the stator magnetic field.
 4. The system of claim 3, wherein the barrier is a wall having an inside surface exposed to non-filtered fuel and an outside surface adjacent to the filtration media such that the wall separates filtered fuel from non-filtered fuel, and wherein the permanent magnet structure is fixed to the inside surface of the wall.
 5. The system of claim 1, the barrier is a wall having an inside surface exposed to non-filtered fuel and an outside surface adjacent to the filtration media such that the wall separates filtered fuel from non-filtered fuel.
 6. The system of claim 1, wherein the outlet of the pump motor assembly is defined by an opening through the barrier.
 7. The system of claim 1, wherein the impeller is disposed in a pumping chamber of the pump motor assembly.
 8. A fuel pump motor system for delivering fuel to an engine, the system comprising: a pump motor assembly comprising: first means for generating a rotor magnetic field, a shaft mounted with respect to the first means such that rotation of the first means rotates the shaft, means for displacing fuel mounted to the shaft, and second means for generating a stator magnetic field, the second means being associated with the first means such that interaction of the rotor magnetic field and the stator magnetic field causes the first means and thus the shaft and means for displacing fuel to rotate thereby moving fuel from an inlet to an outlet of the pump motor assembly, and means for filtering fuel integral with the pump motor assembly and sharing a substantially sealed, non-porous barrier therewith, the means for filtering fuel including filtration media constructed and arranged to filter fuel received from the outlet of the pump motor assembly prior to delivery to an engine.
 9. The system of claim 8, wherein the means for filtering fuel is disposed generally about a periphery of the pump motor assembly to define a housing for the pump motor assembly.
 10. The system of claim 8, wherein the first means includes an armature and windings, such that energizing the windings generates the rotor magnetic field, and wherein the second means includes permanent magnet structure generating the stator magnetic field.
 11. The system of claim 10, wherein the barrier is a wall having an inside surface exposed to non-filtered fuel and an outside surface adjacent to the filtration media such that the wall separates filtered fuel from non-filtered fuel, and wherein the permanent magnet structure is fixed to the inside surface of the wall.
 12. The system of claim 8, the barrier is a wall having an inside surface exposed to non-filtered fuel and an outside surface adjacent to the filtration media such that the wall substantially separates filtered fuel from non-filtered fuel.
 13. The system of claim 8, wherein the outlet of the pump motor assembly is defined by an opening through the barrier.
 14. The system of claim 8, wherein the means for displacing fuel is an impeller disposed in a pumping chamber of the pump motor assembly.
 15. A method of providing a fuel pump motor system for delivering fuel to an engine, the method including: providing a pump motor assembly comprising motor having a shaft, and an impeller coupled to the shaft such that rotation of the shaft and impeller moves fuel from an inlet to an outlet of the pump motor assembly, and generally surrounding a periphery of the pump motor assembly with filter structure such that the filter structure shares a substantially sealed, non-porous barrier with the pump motor assembly, the filter structure including filtration media constructed and arranged to filter fuel received from the outlet of the pump motor assembly prior to delivery to an engine.
 16. The method of claim 15, where the step of providing the pump motor assembly includes providing a rotor including an armature and windings, such that energizing the windings generates a rotor magnetic field, and providing a stator including permanent magnet structure generating a stator magnetic field.
 17. The method of claim 15, wherein the step of surrounding includes ensuring that the barrier substantially separates filtered fuel from non-filtered fuel.
 18. The method of claim 15, further including assembling the fuel pump motor system in a unidirectional manner. 